Method and apparatus for the manufacture of tires



1. A. BOWERMAN. METHOD AND'APPAR'ATUS FOR THE MANUFACTURE OF TIRES. APPLICATION FILED APR. 9. I919.

,327,802, v PatentedzJan. 13,1920.

, f y v ATTORNEYS.

I of sharp UNITED STATES PATENT OFFICE.

J'OSE PH A. BOWEBMAN. OF CHICOPEE FALLS. MASSACHUSETTS, ASSIGNOR TO THE FISKE RUBBER COMPANY. OF MASSACHUSETTS.

CHICOPEE FALLS. MASSACHUSETTS, A CORPORATION OF METHOD AND APPARATUS FOR THE MANUFACTURE OF TIRES.

.To all whom it may concern:

"a citizen of the-United States of America,

residing at Chicopee Falls, in the county of Hampden and State of Massachusetts, have invented certain newand useful Improvements inMethods and Apparatus for the Manufacture of Tiresyof which the followingis a specification.

My invention relates to an improved for manufacturing pneumatic tires,

tires adapted for use on bicycles.

It has for its of tire, and in particular theelimination bends in the fabric at the point where it passes 1 perfection of the adhesion between the headin the 'duced, and having of the valve cot and the terial. The objects will more clearly appear during the description of the invention. In the drawings, I Figure 1 shows a cross-section, on'line 1'-'1 of [Fig 2, of a drum used in the manufacture of the tires, showing a tire: in the procyes of manufacture; I

Fig. 2 is a side elevation of-the same; Fig. 3 is a fragmentary perspective view of a strap used in the manufacture of the tire; F g.

trating the positions'these elements occupy relative to each other.

Fig. 5 is a sectional according to my invention, valve cot in place; and I Fig. 6 is a similar view of a thematic ac cording to the previous method of manufacture. showing the defective positioning of the fabric around the valve cot incident to the former method. I

The rocess for forming tires of this type which as been used. and on whichmy invention is an. improvement. is fully set forth patent to Knadler No. 654,900, dated July 31, 190-0, for method of forming pneudetail of a tire made showing the matic tires, and need not be described in de tail here. In brief, the tire is built upon a drum 10 of a diameter substantially equal to the inner diameter of the tire to be proan axial slot 11 adapted assist in its manipulation. As

object the improvement of I the means and method for forming this type may be tightly sealed over the valve cot and the I .as a small roller, used by strap serves as a spacing tire forming ma- 5 4: is a diagrammatical sectional detail shank projecting through showing the tire forming material andthe valve cot located adjacent the strap,illusscribed in the above patent.

Specification of Letters Patent. Patented J an. 13, 1920. Application filed April 9, 1919. Serial No. 288,820. I

to give clearance for the valve cot slot is denoted by. 0 in the above patent, and its function is-clearly shown in Figs. 4 and 11 thereof.) terial, such as I alternate layers of fabric and uncured rubber, 13and 1i, are laid circumferentially of the drum and are folded into tubular form (Figs. 1 and 2) over a spacing member or strap, 15, preferably flexible and relatively hard. This st ap may have a handle 16 to the layers of fabric are folded over the strap, the latter is drawn along, serving as a spacing member to insure the-tube being'o'f the proper size, and also as a backing against whichthe fold the operator. The member and a backing for the folding andpres'sing of the tire forming material throughout the major however, mustbe folded without a spacing member and pressed without a I backing since the folding of "this "part completely closes the tube, as is fully set forth in the patent above referred to.

away from the shank, is substantially spheroidal, is placed between the layers with the the tire forming material.

' Thus far the method follows that de- My improvement relates to the positioning of the valve cot 12. In the former process,

12. (This The head of the valve cot one side of which, usually that side- I the strap '15 I was flat, and in consequence the action of with a'hand-tool such the hand-tool was to cause a sharp bend of i the fabric layers, as indicated at 17 due to the head of the valve c'ot presenting an elevation to the hand-tool. This sharp bend greatly weakened the fabric and frequently caused ruptures or blow-outs near the valve cot. The bend usuallyoccurred in the form indicated in Fig. 6, but sometimes took the shape of an actual reverse forming material. Either defect caused a 'eakening of the fabric; a weakening of fold in the tire I the tirestructure as a whole due to the.

tendency of the material to straighten out, and imperfect adhesion between the layers of material and between the maternal and the valve cot, as is shown at 19 in Fig.

7 into which the head of the'valvecot, and the heloiv the valve cot.

fabric covering it, may sink. v This permits any-desired amount of pressureloeing 6X1 erteol by the hand-tool around the valve not without danger of any bending of the fabric layers at this point. A. more perfect ashesion between the head of the valve cot and; the fabric layers is also insured. The result attained is illnstratecl in 5, Where it Will be seen that the fabric layers are arranged smoothly both above and This is due to the depression 18 allowing the fabric layers o othertire forming material, to remain, during the"pressing'operation in the natural position the assume :gvhere they lie over the head of the valve cot. I I

ll hile my invention has been described primarily with relation to bicycle tires, it applicable to other cases Where a heatletl valve cot or a patch is to be located between layers of tire forming material.

l'claiin-- 1 1. A spacing member for making tires havirg; a spheroidal depression in one surface thereof. 1

2. A flexible spacing member of rectangular cross-section having a spheroidal depression in one of the surfaces thereof.

The step in a method of making tires comprising placing tire forming material menses circumferentially on a drum; folding the same over a spacing member having a spheroidal depression in one surface there of, locating a valve cot-so that its hesnl is adjacent said depression and its stem passes through the tire forming material, and' forming material into tubular tori r locat- 1 mg; valve cot with its head inclosedl by the tire forming material and its shank passing through a portion-of the tire forming mate rial, and pressing the tire forming material and the head of the Valve cot firmly togetheris'hilepreserving the natural shape of the tire forming material where it lies around the head of the valve cot.

5;. The method of securing in a single tune t e valve cot having a shank anti a h ii. which head has one substantially sphere side; coinprisinglocating the valve cot with its head between ad acent layers of? tire forming n'raterial and itsshank projecting through the tire forming material, and pressing the'heacl of the valve cot and the tiretorming material closely together while keeping the tire formingmaterial tightly against the spheroidal side or the head of the valve cot.

JQSEPH A. BOVVERMAN. 

